[dignick]

i have noticed that the xbox uses the hard drive when changing visualization preset (at least it does on milkdrop), and also when changing tracks (this is playing through smb off a local computer).

if you tell it to, xbmc switches off the hard drive when playing music, but these frequent accesses keep switching it back on.
what i suggest is that the visualizations could be loaded into ram, as all the ones included with a t3ch build are under 700kb, and i have 29mb of ram free under normal use. the visualizations could be loaded into ram when they start, and unloaded when they stop.
as for the track changing hard drive access; is it needed at all? my ipod seems to manage fine for a few tracks, and it's getting the music from the hard drive :p

[jmarshall]

it is necessary, yes.

your ipod caches tracks in advance into ram. this is to save battery life - it has nothing to do with responsiveness.

xbmc does not, nor will it. track order can be changed at any point by the user, as can other images be loaded off disk (thumbs etc.) as can other information (gui textures).

so just leave the harddisk spun up.